Azo dye couplers having two coupling nuclei



United States Patent 2,725,291 AZO DYE COUPLERS HAVING TWO COUPLINGNUCLEI Bruce Graham, Rochester, N. Y., assignor to Eastman KodakCompany, Rochester, N. Y., a corporation of New Jersey N0 Drawing.Application May 1, 1952, Serial No. 285,544 6 Claims. (Cl. 956) to formcolored images upon photographic development are well known. Generally,these color-forming compounds or couplers are colorless or substantiallycolorless. This lack of color is usually desirable where the coupler isto be incorporated in the emulsion layer and the unused coupler remainsafter formation of the colored image. When the coupler is used in thedeveloping solution, it may be colored without detriment to the finalimage, and some colored couplers are known, such as paraphenylazoacetoacetanilide which was disclosed in Mannes and Godowsky Patent2,108,602.

Colored couplers containing a chromophore system which is broken upduring the coupling reaction with the result that the original color ofthe coupler is-destroyed and a new color formed at those points'wheredevelopment occurs, are described in Glass, Vittum and Weissberger U. S.Patents 2,453,661, 2,455,169, 2,455,170 and 2,521,908. These compoundshave an arylazo group on the 4-position of the coupler which splits ofiduring the coupling reaction producing one molecule of azomethine dye(with pyrazolones) or indoaniline dye (with phenols or naphthols).

A difliculty accompanying the use of colored couplers of this type isthat their tinctorial strength is so high that it is necessary to dilutethem with uncolored'couplers-in order to gain a satisfactory ratiobetween the tinctorial strength of the colored coupler and the developeddye.

It is therefore an object of the present invention to provide a methodfor increasing the amount of coupled dye formed from a colored couplerin a silver halide emulsion. A further object is to provide a maskingmethod for color photography in which the proper ratio of tinctorialstrength of the uncoupled and coupled dyes is obtained. A still furtherobject is to provide a photographic film containing novel coloredcouplers. Other objects will appear from the following description of myinvention.

These objects are accomplished by using as colored couplers compoundshaving the structure where R represents a 4-pyrazolone, 4-phenol or4-naphthol nucleus which may be the same or different and which maycontain difierent substituent groups such as alkyl, halogen, carboxylicacid, sulfonic acid, sulfonamide,

alkylamine, acylamine or alkoxy. When R is a phenol,

6 v of p-sulfophenylhydrazine m 600 parts of 1% acetic acid.

2. NH O 0 00 5 N=O C Ha =N NHC obno-O-orm-t l H H NBC 0 am The compoundsof my invention are prepared as follows:

Example 1 .-4-az bis[ 1- (p-sulfophenyl) -3-n-0ctyl- 5 -pyrazolonel1-p-sulfophenyl-3 nbctyl-S-pyrazoline (a). Ethyl pelargonoylacetate(13.8 parts) was dissolved in 600 parts of alcohol. This was added to ahot solution of 11.4 parts This mixturewas refluxed two hours,concentrated to one-half its volume, and cooled. The resulting whitesolid was collected and washed with cold water, 14 parts (a), M. P.265-275". Analysis: Calculated for C1'IH24N2O4S: C, 57.9; H, 6.9; N,7.9; S, 9.1. Found: C, 57.1; H, 6.8; N, 8,0; S, 8.8.

1 p sulfophenyl 3 n octyl 4 isonitroso 5 pyrazolone (b). A solution of2.3 parts of (a) in 100 parts of 50% acetic acid was treated with 0.5part of sodium nitrite at 30. After twenty hours the orange product wascollected, 1.35 parts (b), melts 250.

1-p-sulfophenyl-3-n-octyl-4-amino-5-pyrazolone, its diazotization andcoupling. The nitrosopyrazolone (b), 1.65 parts, in 100 parts of warmwater was reduced over Raney nickel. The catalyst was removed byfiltration and the filtrate was run into a flask containing two parts ofconcentrated hydrochloric acid. The solution was cooled and treated with0.32 part of sodium nitrite. After a few minutes a solution of (a), 1.6parts, in 100 parts of 5% sodium carbonate solution was added. After onehour the solution was made acid with hydrochloric acid and concentrated.to dryness. The dye was extracted from the residue with absolutealcohol and obtained from the latter by drowning in ether. The product(Example 1) is an amorphous, orange powder, 2 parts, which melts 200.

Example 2.-I- (p-sulfophenyl) -3-methyl-4-(1 '-ph enyl-3 benzam into-5'-.ox0-2-pyraz0linyl-4'-az0 -5-pyrazol0ne1-phenyl-3-benzamido-S-pyrazolone (J Am. Chem. Soc, 64, 2133 (1942)),2.8 parts, in 500 parts of 3% sodium carbonate solution was treated with3 parts of 1-p-sulfophenyl-3-methyl-5pyrazolone-4-diazonium enol betainesodium salt (U. S. Patent 2,420,791). The mixture was warmed to 60 C.,then made sufliciently acid with hydrochloric acid that the dyeprecipitated. It was separated by decanting. The dye was triturated withconcentrated hydrochloric acid, which caused it to solidify. It wascollected and dried, 1 part, amorphous, M. ca. 180 C. 1

Example 3.-1-(4-rert-buiylphenoxyphenyl)-3-[a(4-tertbutylphenoxy)propionamido]-4-(1'-p-sulf0phenyl 3- methyZ-5 -ox-2 -pyraz0linyl-4-az0)--pyraz.0lone Prepared as above from 1-p-tert-butylphenoxyphenyl- 3 a ptert outylphenoxypropionamido-S-pyrazolone (U. S. Patent 2,343,702,Example 47). M. P. 184-185 from an aqueous acetic acid-sodium acetatesolution.

Example 4.-4-az0bis-1-p-sulfophenyl-3-methyl-5-pyrazolone Prepared asabove from 1-p-sulfophenyl-3-rnethyl-5- pyrazolone. M. P. 250.

Example 5.-2,2-di-(2,4-di-tert.-amylphen0xyacetamido)-5,5'-dimethyl-6,6'-dichl0r0-a20diphenol Five parts of 2-(diamylphenoxy)-acetamido-4,6-dichloro-S-methylphenol were dissolved ina solution of parts of cone. HCl in 50 parts of acetic acid. ,After 20hours the precipitate of2-(2,4-di-t-arnylphenoxyacetamide)-5-methyl-6-chloroquinone wascollected, washed with water and recrystallized from methanol. Yield:2.5 parts, M. P. 107-108. Anal. calcd. for CHs2ClNO4; N, 80. Found, 7.7.This was converted by treatment with hydroxylamine hydrochloride inalcohol to 2-(2,4-

di-t-amylphenoxyacetamido -4-nitroso-5-methyl-6-chlorophenol. Yield: 2parts, M. P. 203 C. This was reduced to2-(2,4-di-t-amylphenoxyacetamido)4-amino-5-methyl- -chlorop'henol.Yield: 1.5 parts, M. P. 156. This amine when diazotized autocouples.

2- 2,4-DIAMYLPHENOXY -ACETAMINO-,6 DICHLORO5- METHYLPHENOL hour ofstirring, the slurry was diluted with 400 cc. of water, filtered bysuction and the product washed on the filter with 1 l. of water. Solidwas dried overnight at 50 C.

This product was dissolved by stirring on a steam bath with 2 l. ofacetic acid, treated with 5 g. of activated carbon and filtered bysuction through 5 g. of activated carbon. A white product crystallizedfrom the pale orange liquor. Yield: 29 g. (62%), M. P. 151152 C.

Example 6 .--1 -hydr0xy-2 ',5-dibut0xy-4-(4-hydr0xy-2-npentadecyl-phenylazo -2-naph thanilide4-amino-Z-pentadecylphenol, 3.2 parts, in parts of acetic acid wastreated at 0 C. with a solution of 0.7 part of sodium nitrite in tenparts of water. This diazonium solution was allowed to stand twentyhours at 0 C. before. use.

The coupler 1-hydroxy-2',5' dibutoxy-2-naphthanilide, prepared bycondensation of phenyl-l-hydroxy-2-naphthoate with aminohydroquinonedibutyl ether, 4.1 parts, was dissolved in 300 parts of pyridine andcooled to 0 .C. The diazonium solution was added and the mixture wasallowed to stand one hour before being drowned in ice and hydrochloricacid. The solid was collected and recrystallized twice from ligroin,orange dye, M. P. 74-75.

My compounds are particularly useful in a process, such as that ofHanson U. S. Patent 2,449,966, granted September 21, 1948. The Hansonprocess involves a color correction method in which a colored coupler isincorporated in the photographic emulsion layer prior to exposure andupon development is converted into a colored image where the layer wasexposed. The coupler remaining in the unexposed portions of the layerretains its original color, and by suitable choice of the color of theoriginal coupler and the color of the final dye image, a masking orcorrection eifect can be obtained.

The following example illustrates the method of incorporating theazo-bis couplers in a silver halide layer:

3.6 grams of coupler No. l was dissolved in a mixture of 15 ml. ofethanol and 7.5 ml. of 20% aqueous sodium hydroxide solution. Theresulting clear solution was diluted with 200 ml. of water and the pHadjusted to 6.5 by the addition of the necessary quantity of a 2.5%aqueous citric .acidsolution. This produced a clear orange-red solutionwhich was mixed with 250 ml. of a melted sensitized silver halideemulsion. Coatings were prepared in the normal Way on a transparent filmsup port. .When this coating was submitted to standard color processing,a bright magenta dye image was produced, and the yellow colored couplerwas retained in the un exposed areas, serving as a color-correcting dyeimage.

Various photographic developing agents can be employed with the couplersof my invention. The primary aromatic amino developing agents aregenerally suitable including the phenylenediamines and aminophenols. Thealkyl phenylenediamines may be substituted in the amino group as well asin the ring. Suitable compounds are diethylparaphenylenediamine,monomethyl paraphenylenediarnine, dimethyl paraphenylenediamine andpara-aminophenol. These compounds are usuaily employed in the salt form,such as the hydrochloride or the sulphate which are more stable thanthefree amines. Allof these compounds have a primary amino group whichenables the oxidation product of the developer to couple with thecolor-forming compounds to form dye images.

The following developing solution is suitable for de velopinggelatinosilver halide layers containing colored couplers according to myinvention.

Grams 2-amino-5-diethyl-amino toluene HCl 2 Sodium sulphite 2 Sodiumcarbonate 20 Potassium bromide-, 2

Water to 1 liter.

It will be understood that the examples and modifications set forthherein are illustrative only and that my invention is to be taken aslimited only by the scope of the appended claims.

I claim:

1. The method of developing a colored image in a silver halide emulsionlayer which comprises incorporating in said layer a coupler compoundhaving the formula:

\CO HN=NCHO6 Where X is selected from the class consisting of alkylradicals and acylamino radicals and Y is a mononuclear aryl radical,exposing said layer and developing it with a primary aromatic aminodeveloping agent, thereby splitting the azo group and coupling bothresidual portions of said coupler compound at the point of splitting,with the oxidation product of said developing agent to form a dye image,leaving the coupler compound intact in the uncleveloped regions of saidlayer.

2. An unexposed gelatino-silver halide emulsion layer containing acoupler compound having the formula:

\C 0-6 HN==Nl HC6 where X is selected from the class consisting of alkylradicals and acylamino radicals and Y is a mononuclear aryl radical.

3. The method of developing a colored image in a silver halide emulsionlayer which comprises incorporating in said layer a coupler compoundhaving the formula:

where X is an alkyl radical and Y is a mononu'clear aryl radical)exposing said layer and developing it with a primary aromatic aminodeveloping agent, thereby splitting the azo group and coupling bothresidual portions of said coupler compound at the point of splitting,with the oxidation product of said developing agent to form a dyeexposing said layer and developing it with a primary aromatic aminodeveloping agent, thereby splitting the azo group and coupling bothresidual portions of said coupler compound at the point of splitting,with the oxidation product of said developing agent to form a dye image,leaving the coupler compound intact in the undeveloped regions of saidlayer.

5. An unexposed gelatino-silver halide emulsion layer containing acoupler compound having the formula:

where X is an alltyl radical and Y is a mononuclear aryl radical.

6. An unexposed gelatino-silver halide emulsion layer containing acoupler compound having the formula:

=C-CaH17(I1) =N N SOaH References Cited in the file of this patentUNITED STATES PATENTS 2,455,169 Glass et al. Nov. 30, 1948 2,455,170Glass et al. Nov. 30, 1948 FOREIGN PATENTS 586,211 Great Britain Mar.11, 1947 599,377 Great Britain Mar. 11, 1948 627,814 Great Britain Aug.16, 1949

1. THE METHOD OF DEVELOPING A COLORED IMAGE IN A SILVER HALIDE EMULSIONLAYER WHICH COMPRISES INCORPORATING IN SAID LAYER A COUPLER COMPOUNDHAVING THE FORMULA: